Tresca stress evaluation of Metal-on-UHMWPE total hip arthroplasty during peak loading from normal walking activity

Abstract

Ultra-High Molecular Weight Polyethylene (UHMWPE) is one of the most widely used biomaterials for applications in the field of medical devices, especially implants. The use of these materials together with metal is widely used for the combination of materials in total hip arthroplasty as hard-on-soft. Although the use of this combination of materials has been widely adopted, the long-term adverse effects of UHMWPE are a concern for implant users. The selection of the right metal material as a UHMWPE counterpart is crucial to minimize the risk to the patient. Three types of metal materials, namely Cobalt Chromium Molybdenum (CoCrMo), Stainless Steel 316L (SS 316L), and Titanium Alloy (Ti6Al4V) were evaluated using Tresca stress. The computational simulation was chosen with a two-dimensional model using the highest load in normal walking activities as the loading condition. The results show that the combination of materials on CoCrMo-on-UHMWPE bearings gives a Tresca stress value of 7.595 MPa, which is the lowest when compared to the other two combinations of metal and UHMWPE materials.